The Plato IV (1974)

The Plato IV welcomed students at the University of Illinois into the world of computing. Made by Control Data Corp., it featured a display with a 16-by-16 grid infrared touch panel that let students answer questions quickly by touching the screen. The device also helped establish key online concepts: forums, message boards, online testing, e-mail, chat rooms, picture languages, instant messaging, remote screen sharing and multi-player games.